A Federal Communications Commission lawyer faced a skeptical panel of judges today as the FCC defended its repeal of net neutrality rules and deregulation of the broadband industry.

FCC General Counsel Thomas Johnson struggled to explain why broadband shouldn’t be considered a telecommunications service, and struggled to explain the FCC’s failure to protect public safety agencies from Internet providers blocking or slowing down content.

Oral arguments were held today in the case, which is being decided by a three-judge panel of the US Court of Appeals for the District of Columbia Circuit. (Audio of the four-hour-plus oral arguments is available here.) Throttling of firefighters’ data plans played a major role in today’s oral arguments.

Of the three judges, Circuit Judge Patricia Millett expressed the most skepticism of Johnson’s arguments, repeatedly challenging the FCC’s definition of broadband and its disregard for arguments made by public safety agencies. She also questioned the FCC’s claim that the net neutrality rules harmed broadband investment. Circuit Judge Robert Wilkins also expressed some skepticism of FCC arguments, while Senior Circuit Judge Stephen Williams seemed more amenable to FCC arguments. (Williams previously dissented in part from a 2016 ruling that upheld the Obama-era net neutrality rules. Now the same court is considering FCC Chairman Ajit Pai’s repeal of those rules.)

The lawsuit seeking to overturn the net neutrality repeal was filed by more than three dozen entities, including state attorneys general, consumer advocacy groups, and tech companies such as Mozilla and Vimeo.

Is broadband telecommunications?

In order to deregulate broadband, the FCC argued that broadband itself isn’t a telecommunications service and is instead an information service. Under US law, telecommunications is defined as “the transmission, between or among points specified by the user, of information of the user’s choosing, without change in the form or content of the information as sent and received.”

By contrast, US law says an information service is “the offering of a capability for generating, acquiring, storing, transforming, processing, retrieving, utilizing, or making available information via telecommunications.” It’s up to the FCC to determine whether something is a telecommunications or information service, but FCC decisions can be overruled by a court if they aren’t justified properly.

Millett pointed out the importance of the “via telecommunications” phrase in the information service definition, which makes it clear that an information service rides on top of a telecommunications network. For broadband itself to be an information service, ISPs have to offer something more than a pure transmission service.